Back-Ups - cwp vs cwb

I was doing some backing up tonight before our nasty storms roll in. I can get approx. a 4 hour recording session (4.02 GB) onto one DVD. I was concerned about the audio files not saving as well as per the Sonar Reference Guide...
 
"Normal. This is the first option listed and the most common format used for saving project files.

Choosing this will create a Cakewalk Project file with the .cwp file extension. It is important to

remember that Cakewalk Project files do not actually store any audio data, but rather reference

audio files from where they are saved on your computer’s hard drive."
 
but all files DID save creating a good back-up for future emergencies if encountered. Not sure if it was the way I saved or ??? that let the audio files burn to disc.
 
If this way works it will be good, but not sure if I decide to work on it somewhere else if all will go as good.